Car coupler



June 9, 1959 w. J. METZGER 2, 89,

CAR COUPLER Filed July 16, 1957 s Sheets-Sheet 1 IN VEN TOR. WILLIAM J METZGER A TTORNE Y W. J. METZGER Jung 9, 1959 CAR COUPLER 3 Sheets-Sheet 2 Filed July 16, 1957 IN VEN TOR. MLUAM JME TZGER R my ATTORNFY 9 June 9, 1959 I w, J, M'ETZGER 2,889,939

CAR COUPLER Filed July 16, 1957 s Shets-Sheet s ENTOR.

1M5 TZGER ,4 T ORNE Y United States Patent CAR COUPLER William J. Metzger, East Cleveland, Ohio, assignor to NationalM'alleable and Steel Castings Company, Cleveland, Ohio, a corporation of- Ohio Application July 16, 1957, Serial. No. 672,152 7 Claims. (Cl; 213-64)- This-invention relates to railway car couplers and more particularly to the type of coupler which is adapted for vertical as well as horizontal angling.

While the invention has been shown applied. to the A.A.R. (Association of- American Railroads) alternate standard type F interlocking coupler, it will be understood that it may be utilized with other types ofcouplers which are-designed for vertical angling.

In-certain instances, it has been found that crackshave result ineventual total failure of the: wall.

The present. invention corrects thisimproper seating by: locating; the common center of curvature of the inside and. outside surfaces of the rear wall of the coupler shank higher than its present position. With" the center ofi radius so repositioned, proper.- seating; '01: full: bearing contact of the. coupler. shank butt againstrthe yokezor: the draft gear follower is assured. under all; conditions of verticah angling of! the coupler.

Itv istherefore a primary; object of the invention to provide'ina can coupler: of: the type that is; adapted. for vertical angling, at full; bearing: contact between thezrear surface of the coupler. shankand am associated yoke. or draft gearfollowen. whicheverthe case. may be, under all buffingconditions,

Another object. is: toiprovider azcar: conpien including: a coupler shank embodyinga pin. bearing: blockwherein full bearingz contact het-weern the: pin; bearing block' and the; shank. is; assured. under: all draft conditions of thecoupler;

A'- fur-ther object is. to providein. a; can couplenofi the above-mentioned type a fulllbean'ng contact between the butt. endasurlface: of. the coupler shank and. an associated draft gear? follower: or yoke; especially when; the coupler coupler being interchangeable with alli yokes: presently designed: for use; with the AtA-tRl. type F coupler.

A. stilL further objectis'wtoi provideaa can coupler of the aforementioned type: that: avoids; high stress concentrationsat: the shank end of: the. coupler.

Qther: objects: and; advantages. of' the invention will be apparent front the following description taken in conjunction; with: the. drawings; in. which: 1

Fig; 1. is an enlarged, fragmentary, sectional, side eleembodyi'ng the; inventiont with; the. aforementioned coupler pint bearing.- block contained therein. This: view' also shows (indot-dash); the locationof the. forward and rearward curved abutment: surfaces of. the; rear. wall of an -gxisting conventional. coupler. shank and; the: correspondis'iventically angled: and subjected. to a-buffingf'orce; said 'vationalviewt ofthe; rear: portion: of acarjcoupler shank.

2,889,939 Patented June 9, 1959 ing position of the coupler pinv bearing block with respect thereto.

Fig. 2 isa vertical sectional view of, an existing car coupler andi yoke connection. of the type wherein the coupler shank, directly. engages the draft gear forward follower, said coupler being subjected to a slight buffing force. The yoke illustrated is an A.A.R. Y-45. yoke.

Fig. 3 is a fragmentary, sectional, side elevational. view of an existing couplershank and yoke connection wherein.the coupler shank directly engages the yoke, the coupler shank being in horizontal'position with the coupler being subjected to' a bufiing force. The' yoke illustrated is the A.A.R. Y-37 yoke.

Fig. 3a is a view similar to Fig. 3 but showing the .couplershank atthe upper limit. of its free vertical swing.

Fig. 3b is a view similar to Fig; 3a, showing the coupler shank at the lower limit of its free vertical swing.

Fig. 4 is a view similar to Fig. 3 but in which the coupler shank embodies the invention, the coupler being shown free of: buffing and draft forces.

Fig. 4a is a View similar to Fig. 4, but showing a coupler shank which embodies the invention at the upper limit of its free; vertical swing, the coupler being shown subjectedtoa bufling force.

Fig. 4b is a View similar to Fig. 4a, showing the'coupler shank atthe lower limit: of its free vertical swing.

Fig; 5 is a fragmentary, sectional; side elevational view of an existing coupler shank and yoke connection wherein:v the, couplershank directiy engages a forward draft gearv follower, the coupler shank being shown in slightly buffediposition. The. yoke illustrated is the aforementionediAAR. Y45 yoke.

Fig; 5a: is; a view similar to- Fig. 5 with the coupler beingisubjected to a slight bufiing force at the upper limit of its .free' vertical swing.

Fig. 5b is aview similar to Fig. 5a showing the coupler shank. at: the: lower limit: of its free vertical swing.

Fig. 6 is a view similarto Fig. 5 but in which the coupler: shank embodies the invention, the coupler being subjected to a slight buffing: force.

Fig. 6a is. a view similar to Fig. 6, showing a coupler shank which embodies the invention at the upper limit of itsfree' vertical swing.

Fig. 6b is a viewv similar to Fig. 6a but showing the coupler-shank. at: the. lower limit of its free vertical swing.

Referring; to the drawings and particularly to Fig. 2, there is. shown a: coupler 10 having a shank 1 2 and a head-1:4; The: coupler shank shown is that of the A.A.R. typecoupler,. although the invention can be applied to various other types of couplers. The coupler shank 12 i s connectedito a draftgear yoke 16 by means of-verti'cal couplen pin118 which extends through vertical opening 19 i]: the coupler shank and. through aligned openings in; the top" and bottom straps of the yoke. Disposed rearwardlyof pin 18in. coupler shank opening 19'is-pin bearing block 20. Pin 18 and pin bearing block 20' provide for. both lateral and vertical angling of the coupler relative; to: the yoke and car;

The. yokeshown' in Fig. 2 is an A.A.R. Y-45 yoke. Rear; wall! 24 of the shank defines the rearward extremity of pin-receiving opening 19 and comprises outer or rear surface 22. Surface 22 is spherically curved about; a point located substantiallyat the intersection of the vertical axis of pin 18 and the longitudinal center line XX of the shank and is adapted for engagement with complementary curved surface 26 on front follower 28i-ofthe draft gear. Rearwardly' facing surface 30 on hearing block 20 is spherically curved about the same center of curvature assur-faces 22 and 26, and is adapted for engagement with" complementary curved surface 32 the aforementioned abutment element or front follower 28, cushioning mechanism 34 and a rear follower (not shown). The draft and buffing forces are transmitted to and cushioned by the draft gear in the usual manner.

In Figs. 3 through 4b, there is shown a coupler shank and yoke connection similar to that of Fig. 2 except that the yoke is an A.A.R. Y-37 yoke. In this latter case the coupler shank is adapted to engage an integral abutment element of the yoke, comprehensively designated by numeral 35.

The type F coupler is currently used with either the A.A.R. Y-37 yoke or the aforementioned A.A.R. Y-45 yoke. In both cases, as previously mentioned, cracks have sometimes developed in rear wall 24 of the coupler shank. These cracks are caused primarily by the improper seating of the rear surface 22 of the coupler shank against follower 28 in the case of the Y-45 yoke, or against integral wall 35 in the case of the Y-37 yoke. This improper seating causes a concentration of stresses on wall 24 which may eventually develop into a complete fracture of the wall.

The cause of the improper seating in an existing type F coupler shank and Y-37 yoke arrangement is illustrated in Figs. 3, 3a and 3b, which show the position of the parts when the coupler is subjected to a buifing force. The center of curvature of rearwardly facing surface 22 of the coupler shank and complementary forwardly facing engaging surface 36 on integral wall 35 of the yoke is located substantially at the intersection of the vertical axis of pin 18 and the horizontal axis of shank 12. The center of curvature of rearwardly facing surface 30 on pin bearing block 20 and complementary forwardly facing surface 32 on shank rear wall 24 is also located at the same point as the aforementioned center of curvature of surfaces 22 and 36. Thus, when the coupler is in a substantially horizontal position and is subjected to a buffing force, as shown in Fig. 3, full bearing contact occurs between surfaces 22 and 36. Moreover, when the coupler is subjected to a. draft force (this condition however not being shown), full bearing contact between surfaces 30 and 32 will occur. This full bearing contact would ordinarily continue to exist for all positions of vertical angling of the coupler so long as the coupler is angled about the center of curvature of these surfaces. However, because of the fact that the F coupler is head heavy, top surface 38 of coupler shank 12 is initially in contact with top wall 40 of yoke 16 and remains in contact when the coupler is angled vertically and subjected to bufiing or draft forces. Because of this, the coupler shank angles vertically about its contact with wall 40 of the yoke and not about the center of curvature of surfaces 30, 32, 22 and 36. Accordingly, in buff only the lower portion of shank rear wall surface 22 contacts surface 36 on the yoke when the coupler is vertically angled, as shown in Figs. 3a and 3b, and thus the lower portion of shank rear wall 24 receives all of the bufiing force. Likewise, when the coupler is subjected to a draft force, all of the force is concentrated at or near the upper portion of inner surface 32 of shank rear wall 24. However, since the bufling impacts applied to the coupler are generally of a substantially greater intensity than the impacts during draft, most of the cracking of rear wall 24 has been found to occur on the lower portion thereof. It will be noted in Figs. 3a and 317 that as the coupler angles, pin bearing block 20 engages bottom wall 42 of the yoke and thus is prevented from moving downward a suflicient amount to enable full contact between surfaces 32 on the shank and surface 30 on the pin bearing block.

In order to eliminate the aforementioned stress concentrations on rear wall 24 of the coupler shank, full bearing contact between surfaces 22 and 36 and between surfaces 30 and 32 must be provided under all conditions of vertical angling of the coupler. It will be understood that the same problem would exist if the coushank. It will also be noted pler were shank heavy rather than head heavy, in which case the coupler shank would angle about its point of contact with the bottom wall 42 of the yoke rather than with the top wall, as shown.

In accordance with the invention, the common center of curvature of outer and inner surfaces 22 and 32, respectively, on shank rear wall 24 has been located above its present position to provide full bearing contact for all positions of the coupler, including vertically angled position, during draft and buffing operations. Referring to Fig. l, the radii of surfaces 22 and 32 (shown in dotdash) as they are currently positioned on an existing coupler shank, are represented by vectors b and b, respectively. Surfaces 22 and 32, repositioned in accordance with the invention, are shown as surfaces 22' and 32, the radii of these repositioned surfaces being represented by the vectors a and a, respectviely.

It will be noted that these repositioned surfaces have their common center of curvature A higher than the pre vious center of curvature B. New center of curvature A is disposed upwardly from the longitudinal center line XX of the shank and nearer the top wall thereof in contrast to the previous center of curvature B which was located substantially at the intersection of the longitudinal center line XX of the shank 12 and the vertical axis of pin 18. The most satisfactory results for the type F coupler have been obtained by positioning the new center of curvature A of an inch above the old center of curvature B, although it will be understood that this exact figure may not be applicable to all types of coupler-yoke connections.

Fig. 1 also shows (in solid lines) the position pin bearing block 20 takes with respect to shank 12 when it is engaged by coupler shank rear wall 24 having the raised center of curvature, the position of the pin bearing block, when associated with a coupler shank having an existing or conventional center of curvature, is shown in dot-dash. It will be noted that in the latter position, pin bearing block 20 is located substantially lower in opening 19 in the shank.

Reference is now made to Figs. 4, 4a and 4b, which correspond generally to Figs. 3, 3a and 3b, respectively, but which illustrate a coupler shank and Y-37 yoke connection embodying the invention. In Fig. 4 the coupler is not subjected to either a bufling or draft force and it will be noted that there is sufiicient space between shank bottom surface 44 and yoke bottom wall 42 for the shank to move downwardly so as to permit seating of the butt end of the shank against the abutment portion of the i seen, therefore, that in the Fig. 4 position, the center of curvature of shank and surface 22' is actually disposed above the center of curvature of surface 36 on the yoke. In Fig. 4a, wherein the coupler is shown subjected to a buffing force when at the upper limit of its free vertical swing, it will be noted that with top surface 38 of the shank in contact with top wall 40 of the yoke, there is full bearing contact between shank rear surface 22 and complementary surface 36 on the yoke. Also, in Fig. 4b, wherein the coupler is subjected to a bufiing force when at the lower limit of its free vertical swing, top surface 38 of the shank is still in contact with top wall 40 of the yoke and there is a full bearing contact between shank rear wall surface 22 and surface 36 on the yoke. This full bearing contact will exist between surface 22' on the shank and engaging surface 36 on the yoke, irrespective of the degree of vertical angling of the coupler in Figs. 4a and 4b that the width of the gap between surface 30 on pin bearing block 20 and inner surface 32' on shank rear wall 24 is constant over the entire contact area of these surfaces such that a Furthermore, it will be seenin Figs. 4a and 4b that pin bearing block 20 remains positionedsubstantially midway between top and bottom walls. 40" and 42 of the yoke during vertical'angling of the coupler'to thus ensure; full surface contact in draft between surfaces 30 and 3-2. Spring means (not shown) extending between the shank and block 20 ordinarily maintains the latter in centered position.

In Figs. 5, a and 511, there is shown an existing F coupler shank and Y-45 yoke arrangement. In Fig. 5 the coupler is being subjected to a.slight' buffing force and it will benoted thatshank top wall 38 is in contact with yoke topwall 40 andthere is a fullbearing contact betweensurfaces 22 and 26. This desirable, full bearing condition exists, however, only when the. coupler shank is substantially horizontal; In Fig, 5a the parts are shown in a, position wherein the coupler. is at the upper limit of its free vertical swing, withshank. top. wall 38 in contact with yoke top wall. 40; full bearing contact between surfaces 22 and 26 can exist. only if follower 28' is displaced downward to the theoretical position shown, where it contacts yoke bottom wall 42. Alsoin Fig. 5b, with the coupler at the lower limit of its free vertical swing, full bearing contact between surfaces 22 and 26 is achieved only if follower 28 is again displaced downward to the theoretical position shown, where it contacts yoke bottom wall 42. This, of course, is due to the fact that the. coupler angles vertically about its. point of contact with yoke top wall 40 as previously explained. In actual practice, however, the initial compression of the draft gear, plus the additional compression resulting from the bufling force applied to the coupler, generally forces follower 28 against the shank end with sufficient force to prevent the follower from being displaced vertically to the theoretical positions shown in Figs. 5a and 5b and therefore only point contact, and not full surface engagement, occurs between the surfaces 22 and 26 to thus cause a concentration of stress and eventual failure of the rear wall of the coupler shank. Figs. 5a and 5b also illustrate the improper seating of pin bearing block 20 with inner surface 32 of shank rear wall 24. It will be seen that block 20 cannot move down to provide proper seating between surface 30 on the block because block 20 and forwardly facing surface 32 on the shank rear wall 24 is already in contact with bottom wall 42 on the yoke. A concentration of stress, therefore, occurs which eventually may result in failure of rear wall 24 of the shank.

Figs. 6, 6a and 6b correspond generally to Figs. 5, 5a and 5b, respectively, but illustrate a coupler shank and Y-45 yoke connection embodying the invention. As aforedescribed in connection with the Y-37 yoke and coupler shank arrangement, the center of curvature of the outer and inner surfaces 22' and 32 of the rear wall of ."the shank have been raised a predetermined amount to thus ensure full surface contact between outer surface 22 on the shank and complementary surface 26 on the front follower 28 of the draft gear and between inner surface 32' and complementary surface 30 on pin bearing block 20, irrespective of the angling movement of the coupler.

In Fig. 6 the coupler is shown as being subjected to a slight bufling force and it will be seen that full surface engagement occurs between outer surface 22' on the rear Wall 24 of the coupler shank and complementary surface 26 on front follower 28 of the draft gear. It will also be readily understood that in draft, full surface engagement between inner surface 32' on the shank and complementary rearwardly facing surface 30 on pin bearing block 20 will occur. It will be noted in Fig. 6 that a clearance, as at 46, exists between the top surface 38 of the coupler shank and the top strap 40 of the yoke when the coupler is in a substantially horizontal position.

Figs. 6a and 6b illustrate a Y-4S yoke and coupler shank arrangement in which the coupler is subjected to a slight buifmg force and is at, respectively, the upper 6 and lower limits of its free vertical swing. It will be observed; that in both instances, fullbearing contact is obtained between, the engagingsurfaces 22' and 26 on the rear wall 24 andi follower'28, respectively; It'will also be apparentthat in draft, full surface contact will occur between the engagingsurfaces 32' and 30- onthe rear wall 24 and pin bearing'block 20. Accordingly, no particular points; or" areas of stress concentration occur to; cause failure of. the shank rear wall in either draft orbuif irrespective of the vertical angling movement of the coupler. It will be observed from Figs. 6a.and 6li'that follower ZSremainssubstantially midway between. upper and lower walls 40 and 42 of the yoke upon vertical angling movementof the coupler, yet full surface contact between surface 22' on the. rear Wall 2.4 and complementary surface, 26' on the follower 28'continues' to exist.

The improved coupler shank can be; used with all existing types of yokes andall other attachments designed for use with the A.A-.R. type F coupler.

While the invention has been describedparticularly with respect to a coupler shank wherein the rearward extremity; or butt end thereof" is spherically curved, it will'be understood that the invention concerns the vertical angling action of the coupler and accordingly will work equally as well with a coupler shank in which the butt end thereof is only radially curved; v

From the foregoing description and accompanying drawings it will be readily understood that a coupler shank and draft gear yoke arrangement is provided for the type of coupler adapted for vertical angling that ensures full surface engagement in buff between the end of the coupler shank and the front abutment in the yoke irrespective of the vertical angling of the coupler. It will also be understood that the invention provides, in a coupler of the aforementioned type which includes a pin bearing block, full surface engagement in draft between the coupler shank rear wall and pin bearing block, irrespective of the vertical angling movement of the coupler. Thus, the invention provides a coupler shank wherein all points or areas of high stress concentration at the butt end thereof, due to improper seating during vertical angling, are eliminated and thereby provide a relatively stronger shank.

The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. In a car coupler shank adapted for vertical angling and comprising a rear wall having a curved butt end surface, said surface in vertical cross-section having a center of curvature disposed upwardly of a horizontal plane passing through the longitudinal center line of said shank.

2. A car coupler comprising a head and a shank, a rear wall and a vertical pin-receiving opening on the rearward portion of said shank, said opening defining a forward facing curved surface on one longitudinal end of said rear wall, a rearwardly facing curved surface on the opposed longitudinal end of said rear wall, said curved surfaces having a common center of cuwature disposed upwardly of a horizontal plane passing through the longitudinal center line of said shank.

3. A car coupler comprising a head and a shank, a rear wall and a vertical opening on the rearward portion of said shank, said opening defining a forward facing curved surface on one longitudinal end of said rear wall, a rearwardly facing curved surface on the opposed longitudinal end of said rear wall, said curved surfaces having a single and common center of curvature, said center of curvature being vertically spaced from a horizontal plane passing through the longitudinal center line of said shank.

7 7 4, The combination of a car coupler and a yoke connected together by a vertical pin, said coupler including a shank, outer and inner longitudinally spaced curved surfaces defining a rear wall on said shank, said yoke ineluding an abutment element having a forwardly facing curved surface, said inner and outer curved surfaces having a common center of curvature disposed upwardly of a horizontal plane passing through the longitudinal center line of said shank, said outer surface complementally engaging said'forwardly facing surface during all positions of said coupler when bufiing' forces are applied.

5. The combination as claimed in claim 4 further characte riz ed by the fact that a pin bearing block is disposed between said vertical pin and said wall, said block having a rearwardly facing curved surface complementally engaging said inner curved surface of said wall during all positions of said coupler when draft forces are applied.

6. The combination of a car coupler and a yoke connected together by a vertical pin, a shank on said coupler having a rear wall defined by inner and outer longitudinally spaced curved surfaces struck from a common cen ter of curvature disposed upwardly from a horizontal plane passing through the longitudinal center line of said shank, a front abutment wall on said yoke defining a forsaid coupler, said outer surface complementally engaging said forwardly facing surface when said coupler is vertically angled and subjected to buff forces, and said inner surface complementally engaging said rearwardly facing surface when said coupler is vertically angled and subjected to draft forces.

' 7. The combination of a car coupler and a yoke connected together by a vertical pin, a shank on said coupler having a rear wall defined by inner and outer longitudinally spaced curved surfaces struck from a common center of curvature disposed upwardly from a horizontal plane passing through the longitudinal center line of said shank, a followercarried by said yoke and having a forwardly facing curved surface, a bearing block having a rearwardly facing curved surface interposed between said rear wall and said vertical pin, said center of curvature forming a pivot point for vertical angling movements of said coupler, said outer surface complementally engaging said forwardly facing surface when said coupler is vertically angled and subjected to buff forces, and said inner surface complementally engaging said rearwardly facing surface when said coupler is vertically angled and subjected to draft forces;

References Cited in the file of this patent UNITED STATES PATENTS 2,645,361 Wolfe July 14, 1953 

